1. Field of the Invention
The present invention generally relates to a magnetic head, typically used in a magnetic disk drive, and more particularly to a thin film magnetic head.
2. Description of Related Art
Recently, a recording medium with a higher coercive force is required, due to an ever-increasing recording density of a magnetic disk drive. Under such circumstances, the magnetic core of a write head is formed from a material with a high-saturation magnetic flux density (Bs) that generates a strong magnetic field.
One of the examples of the material having a high saturation magnetic flux density (Bs) is a CoNiFe alloy (Bs>1.7 T). This Bs value is greater than that of a Ni45Fe55 alloy (Bs: 1.6 T), which has been used in magnetic core materials. CoNiFe alloys are described in, for example, Japanese published patent application, JPA 6-89422, JPA 8-241503, JPA 6-346202, and JPA 7-3489. Further, Japanese Patent JP 2821456 describes a method for fabricating a magnetic film with high Bs values by plating in a plating solution that does not contain saccharin sodium. As another example, in Japanese published patent application, JPA 2002-280217, materials based on Co—Fe alloys is disclosed as having a high Bs value.
For a magnetic disk drive capable of high-density recording, a magnetic head with a magnetic core that generates a stronger magnetic field is required. Recently, forming a stable magnetic core with a thick film, using a material that has a high saturation magnetic flux density (Bs) is under study. Such material is required to generate a strong magnetic field that permits writing on a recording medium having a high coercive force.
However, even with the reported CoNiFe material we could not stably make a luster film with enough thickness by electroplating, because of white turbidity, bumps of the film surface. Also, Co—Fe two element series alloy did not have corrosion resistance.
Accordingly, what is needed is a magnetic head having a magnetic core that is capable of generating a stronger magnetic field, and at the same time having high corrosion resistance.